Objective:To study the relationship between deletion of P16 gene and occurrence and progression of astrocytomas. Methods: The techniques of polymerase chain reaction (PCR) and immunohistochemistry were used to detect the deletion of exon2 of P16 gene and expression of P16 gene in 52 cases of Brain astrocytoma.Results: The deletion rate of exon2 of P16 gene in the tumors analyzed was 34.6%. Most of them with deletion of exon2 of p16 gene were high grade astrocytomas (grade Ⅲ 42%, grade Ⅳ 50%). 61.5% of the tumors were absent from expression of p16 and the deletion rate of p16 protein increased with the grade of astrocytoma (X2=10.83, P＜0.005). Conclusion: Deletion of p16 gene and protein may correlate with the malignant progression of astrocytoma.